1. Field of the Invention
This invention relates to isolation systems and more particularly to coal fired steam electric generation plant absorber tower isolation systems.
2. Description of the Prior Art
Because of increasing environmental standards, coal fired steam electric generation plants have been required to use absorber towers for the removal of SO.sub.2 from the flue gas. Continuous operation of the steam electric plant is very important, and the reliability and need to perform routine maintenance of the absorber towers is such that, as direct components of steam electric generation plants, they may cause an unacceptable number of plant shut-downs. Therefore, it is necessary to be able to isolate absorber towers for repair while maintaining the operation of the plant with as many absorber towers as possible in order to satisfy environmental standards. There has been some suggestion of possibly using louver dampers, guillotine dampers, or butterfly valves. Further, there is suggestion of using a diversionary gate to direct flow in one direction or another. None of these methods have proven acceptable for complete isolation such that an individual may safely perform maintenance inside an inlet duct or absorber tower. Further, shut-down and start up procedures cannot be implemented in an acceptable manner.